4R70W Mods/TSBs Before Install?

[RandomNerd2000]

I picked up a transmission today out a 2000 5.0 Mountaineer AWD, and before I install it I'm curious if there's anything outside of a pan drop and filter change I need to do or check for? In think it's good to bolt in but I'd like to know for sure, it has 131K miles on it.

 

[SoHK_alumni]

Certainly take the time to pop out the accumulator piston and check the bore and the springs.

Broken accumulator springs is a common failure in the 4R70W

 

[nathan mayden]

I would put a shift kit in and definitely check servo bores and definitely get another torque converter.

 

[RandomNerd2000]

Certainly take the time to pop out the accumulator piston and check the bore and the springs.

Broken accumulator springs is a common failure in the 4R70W

As far as I know that was fixed in 98 almost in it's entirety, my 99 is the only post 98 4R70W out of an army of them I've ever seen with a hard shift from 1-2, and it looks like it's been worked on somewhat so I'm curious if that was a mistake caused issue.

I would put a shift kit in and definitely check servo bores and definitely get another torque converter.

Converter is accounted for, it's an easy fix while the trans is out. I'll be checking the bores though, as well as any other checks I get told to.

 

[Dono]

My 00 4r70w broke its 1-2 accumulator spring. I don't think its exactly common either, but does happen. I'm not sure if they break from fatigue, or if its test a weak spring.

My 'update' while the pan was off was to replace the 1-2 and 2-3 accumulators along with a lentech valve body.

If I were you, just do the fluid and filter change. inspect the bottom of the pan while its out. if theres all kinds of material in the bottom of the pan, you will have that sinking feeling in your gut as you will know what's next.

 

[RandomNerd2000]

My 00 4r70w broke its 1-2 accumulator spring. I don't think its exactly common either, but does happen. I'm not sure if they break from fatigue, or if its test a weak spring.

My 'update' while the pan was off was to replace the 1-2 and 2-3 accumulators along with a lentech valve body.

If I were you, just do the fluid and filter change. inspect the bottom of the pan while its out. if theres all kinds of material in the bottom of the pan, you will have that sinking feeling in your gut as you will know what's next.

Well I stuck my finger in the fluid through the dipstick hole and it came out to not smell burnt or really have any alarming thing about it at all, it was actually really encouraging, it seemed to be rather new fluid, not brand new fluid though but not black or burnt smelling either, it smelled new to be honest though. You're the only person I've ever heard of having a later model 4R70W break the spring from 1-2 outside of myself, assuming that's my 2WD's hard 1st-2nd.

 

[boominXplorer]

Well I stuck my finger in the fluid through the dipstick hole and it came out to not smell burnt or really have any alarming thing about it at all, it was actually really encouraging, it seemed to be rather new fluid, not brand new fluid though but not black or burnt smelling either, it smelled new to be honest though. You're the only person I've ever heard of having a later model 4R70W break the spring from 1-2 outside of myself, assuming that's my 2WD's hard 1st-2nd.

I had an 01 f150 with the 4r70 and it broke the 1-2 spring into about 5 peices before I tore it apart to fix it. I also broke my 2-3 spring in my 00 mountaineer (while spraying a 100 shot)

 

[CDW6212R]

With a trans out, I'd replace all of the shift solenoids, accumulators, and springs that are easily bought, and do the little VB things that Sonnax has for most automatics. Those are just basic things any used trans needs, at any mileage. The VB kits are deeper subjects, do those as you want to or need. The pan gasket will last forever, take care of it. A deeper pan is wise for a keeper vehicle, or high stress use like towing etc.